碩士 / 國立高雄海洋科技大學 / 漁業生產與管理研究所 / 98 / The bottom trawl is one of the important inshore fisheries in Pingtung, Taiwan. However, it frequently damages the breeding habitats and makes a great impact on the fish resources so that the government implemented the closed fishing areas within 3 nms from the coastline for trawlers. In order to understand the differences of catche components between inside and outside of closed fishing areas, this study used the shrimp beam trawl to carry out the experiments with 10m, 20 m isobaths within 3 nms and 40 m, 60 m, 80 m, 100 m isobaths outside the 3 nms from 2008 to 2009 for analyzing the fish composition at the same isobaths. The analysis results are as follows:
A total of 86 fish species, 27 shrimp species, 32 crab species, and 6 cephalopod species were sampled.
1. The results on usage of multiple variables during the experiment whatever in the cluster, similar and dissimilarity contribution analysis, the dominant species on places inside 3nms and outside 3nms showed significantly different (p<0.05). Such changes are mainly influenced by the composition changes of fish and shrimp. These fishes are Epinephelus coioides, Pomadasys kaakan, and Nemipterus japonicas. The shrimps are Penaeus semisulcatus, Trachypenaeus curvirostris, and Penaeus japonicas.
2. Species diversity on 10 m, 20 m isobaths within 3 nms and 40 m, 60 m, 80 m, 100 m isobaths outside the 3 nms showed no significant different as in a steady state. There is no significant difference from the ANOSIM analysis and Cluster analysis is not able to separate the communities into different groups.
3. Dominant species of Fish and shrimp caught in the first to fourth and fifth to seventh voyages are not similar, crabs and cephalopods dominant species change little. The voyages after the fifth voyage are carried out after the Morakot typhoon. The ANOSIM analysis it shows a significant difference in fish structure before and after Morakot typhoon.
It is suggested that the main reason for this change is due to the flood of Morakot typoon in 2009.
| Identifer | oai:union.ndltd.org:TW/098NKIM8451008 |
| Date | January 2010 |
| Creators | Sian-Yin Jhou, 周先音 |
| Contributors | Chao-ching Chen, 陳朝清 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 84 |
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